Pump stroke gauge



July 9, 1940. .1. L. EDELEN PUMP STROKE GAUGE Filed Sept. 26, 1939 K 34 FlG.2.- FIG.3.

INVENTOR 7 JAMES L. EDELEN WA LUZQQK ATTORNEY Patented July 9, 1940 UNITED STATES 2,207,396 PUMP STROKE GAUGE James L. Edelen, St.

Louis, Mo., assignor to Carter Carburetor Corporation, St. Louis, Mo., a corporation of Delaware Application September 26, 1939, Serial No. 296,552

4 Claims.

This invention relates to gauges and consists particularly in a novel device for measuring and adjusting the maximum stroke of the accelerating pump piston in internal combustion engine carburetors. This application is a continuation, in part, of an application, Serial No. 173,867, filed November 10, 1937, in the name of the present inventor.

Accurate determination of the accelerating discharge in carburetors is an important factor in calibration and servicing and this depends, mainly, on the length of stroke of the pump piston. To facilitate such determination, particularly when carburetors are installed and serviced in the field, it is desirable to have available simple and efficient means for determining whether or not the piston stroke is correct without disassembling the carburetor.

Accordingly, an object of the present invention is to provide a novel gauge which may be readily applied to a predetermined, movable point on the pump piston or operating connection and a stationary point adjacent the piston to measure the distance therebetween for any desired setting of the piston.

Another object is to provide means for magni fying the movement of the pump piston to facilitate measuring the same and accurately determining the position of the predetermined piston rod point, for instance, when the piston is in its fully charged or returned position.

These objects and other more detailed objects hereafter appearing are attained by thedevices illustrated in the accompanying drawing in which:

Fig. 1 is a view of a carburetor showing one form of the novel gauge applied thereto.

Fig. 2 is a side view of the gauge.

Fig. 3 is a vertical sectional view taken at 90 to Fig. 2.

,Fig. 4 is a side View of a modified form of gauge.

Fig. 5 is a vertical section showing the gauge in Fig. 4.

Figs. 6 and '7 are horizontal sections taken on the corresponding section lines of Fig. 5.

The carburetor shown in Fig. 1 includes the usual float bowl I enclosing an accelerating pump cylinder 2, having a pumping piston 3 reciprocable therein. Suitable passages and valves (not shown) are provided permitting drawing fuel from the bowl into the pumping cylinder and forcing the same into the mixture conduit in barrel 4 when the piston is reciprocated. A piston rod 5 projects upwardly from piston 3 through bowl cover 6 and is secured by a link 1 to a lever 8, pivoted at 9 on a post I0 projecting above the bowl cover. 'The other end'of lever 8 is secured by means of a link I l to an arm l2 rigid with throttle shaft l3. Suitable means (not shown) are provided for operating the throttlevalve.

The gauge shown in Figs. 1-3 comprises a sta-. tionary base member 34 having a forked projection orjaw 34a. Secured to the base portion, as at 35, is an upright, stationary screw 36, which carries a threaded sleeve 31 forming a nut. A knurled cup 38 is rigidly secured to the upper extremity of sleeve 31 so that rotation of the cup also rotates the threaded sleeve propelling the same along screw 36.

Also rigidly secured to base 34 is a guidebarrel 39 which projects between sleeve 31 and hand grip cup 38. A movable jaw 4!] has a collar 4| rotatably receiving sleeve 3! and secured in position thereon by a nut 42. Jaw 40 slides in a slot 43 in barrel 39 and is held against rotation thereby. Inscribed on the surface of barrel 39 and extending spirally therearound are the gang.- ing indicia 44, which, by reference to the index marker on the lower edge of cup 38, indicate on a magnified scale the relative movement and positioning of jaws 34a and 40. Screw SQmay be conveniently made of four threads to the inch and then if the surface of barrel 39 is provided with [6 markings 44 along an inch of its circumference, movement of index point 45 between any two of the marks 44 will directly indicate a relative jaw movement of Such magnification is desirable since the pump stroke, in most cases, does not exceed about In operation, forked jaw 34a. is applied to a pad 46 on bowl cover 6 surrounding piston rod 5 and movable jaw 40 is then placed on top of rod 5, as shown in Fig. 1 and the relative positioning of the gauged points read from the scale. The piston rod may be placed in any predetermined position for gauging, but preferably it will be lifted to the fully charged position of the pump. Suitable adjustments can then be made to secure proper positioning of the piston and to obtain the desired maximum pump stroke.

The form in Figs. 4-7 is similar to that in'the first, but is generally simplified in that the screw and guide are both formed by an elongated barrel. The modified gauge comprises a body or barrel having a stationary base portion 50 with forked jaw 5|, 2. smooth-walled lower portion 52, and a threaded, somewhat enlarged upper portion 53 receiving a knurled nut 54. A deep slot 55 extends the length of the body portion and receives a slider 56 having a movable gauging finger 51 at its lower end and a second finger 58 at its upper end, both projecting outwardly beyond the surface of the body portion. Upper finger 58 extends into an internal annular slot 59 in nut 54 so that rotation of the nut will cause the slider to be drawn along the barrel. Slot 55 is formed T-shape in section, as best shown in Figs. 6 and 7, and slider 56 has lateral lugs 60 extending into the cross arm portions thereof for maintaining the assembly.

A series of gauging points and ordinals' 62 are inscribed around the flat top of the threads in upper portion 53 of the gaugebo'dy and these cooperate with an index point 63 on knurled nut 54 to indicate the relative movements and positioning of jaws and 51. The measurement of the screw threads and positioning of the gauging in dicia may be arranged as in the first form to provide a suitably fine adjustability of the gauge. The use of the second form is the same as in the case of the first, forked jaw 5| being placed upon the bowl cover adjacent the pump piston rod and movable jaw 51 being adjusted to engage the top of the piston rod in the position for which adjustment is prescribed.

The device provides a readily applicable standard for adjusting carburetors in the field and is sufficiently simple and durable for use as a service tool. Various modifications may be made as will occur to those skilled in the art and the exclusive use of all such modifications as come within the scope of the appended claims is contemplated.

I claim:

1. In a gauge, stationary structure including a base member to be placed against one of two parts to be gauged, a screw projecting from said base member, a barrel surrounding said screw, said barrel having a slot, a nut inside said barrel and threaded on said screw, said nut having a handle part extending on the outside of said barrel, a gauging finger to be placed against the other part to be gauged, said finger being movable in said slot with said nut and being held against rotation by said slot, and scale markings on said barrel and an index point on said handle part to indicate the relative position of said base member and said finger.

2. In a gauge, a base member arranged to be placed against one of two parts to be gauged, structure rigid with and projecting from said base member, said structure having a part with a longitudinal slot and a threaded part, a nut threaded on said threaded part, and a member longitudinally movable along said slotted part and maintained against rotation thereby, said movable member having a gauging finger projecting through said slot and a portion forming a bearing on said nut for transmitting longitudinal movement of said nut thereto, there being scale markings and an index point on said elongated structure and said nut to indicate the relative positioning of said base member and said finger.

3. In a gauge, a stationary base member including an element to be placed against one of two parts to be gauged, structure rigid with and projecting from said base member including a slotted guide and a screw, a rotatable nut threaded on said screw, and a movable member including a gauging finger extending through said slotted guide and held against rotation thereby and a part having a bearing on said nut for longitudinal movement therewith, there being scale markings on said projecting structure and an index point on said nut to indicate the relative positions of said base element and said finger.

4. In a gauge, a stationary base member including an element to be placed against one of two parts to be gauged, elongated, hollow structure rigid with and projecting from said base member, said structure having a longitudinal slot and at least a part thereof being externally threaded, a nut threaded on said threaded part and having an internal annular groove, and a member movable longitudinally in said structure and having a gauging finger extending through said slot and held against rotation thereby and a second finger extending through said slot into said annular groove for transmitting longitudinal movement of said nut to said movable member, there being scale markings on said threaded part and an index point on said nut to indicate the relative positions of said base element and said finger.

JAMES L. EDELEN. 

